BARCELONA, SPAIN—Forget every rumor you've heard about the Samsung Galaxy S5. It doesn't come in two models, it's not really a new design, and it doesn't look like Touchwiz is changing anytime soon. At Samsung's "Unpacked 5" Mobile World Congress press event, we got a chance to play with Samsung's newest flagship. Before they arrive by the truckload to your local smartphone purveyor, we figured we'd give you a sneak peek at the company's latest.

Have you seen a Galaxy S4? Good, then you're most of the way there. Before the launch of the Galaxy S5, Samsung blamed the lower-than-expected sales of the Galaxy S4 on the similar appearance between it and the Galaxy S3, but unless you flip the S5 over, the S4 and S5 are nearly identical. From the front the S5 is a clone of the S4, except it's a little bigger. The removable back is really the only place Samsung has made changes. The "brushed plastic" back of the S4 has been replaced with a weird "perforated" golf ball pattern. It doesn't really look any better in person than it does in pictures—it just seems strange and out-of-place on an electronic device. While the look of the back is new, on the materials front it's still the same old hard plastic. The public demo units got greasy really quickly.

Like the NotePro and TabPro, the Galaxy S5 switched the hardware button set from Menu, Home, and Back to Recent Apps, Home, and Back, which brings Samsung a little closer to the recommenced Google layout. The S5 got things backwards, but at least the menu button is finally dead.

The lock screen, locked with a fingerprint. The dots at the bottom are telling you to place your finger there.

The lock screen, locked with a fingerprint. The dots at the bottom are telling you to place your finger there.

Teaching the fingerprint reader your fingerprint.

Samsung's "My Magazine" flipboard app. It now lives on the left panel of the home screen, similar to how you open Google Now on the Nexus 5.

The crazy new settings screen.

The new notification panel with round icons.

A USB3 port!

Just like Sony devices, the S5 is waterproof thanks to this port flap.

The side, it's still fake chrome.

The back comes in blue, black, and gold.

The S5 with the back off. The gray rubber gasket on the back keeps it waterproof.

On the hardware features front, Samsung has added a fingerprint scanner and a heartbeat reader. The fingerprint scanner is invisibly embedded in the home button and works a lot like the swipey fingerprint readers on a Windows laptop. While a swipe reader will never be as good as the iPhone 5S's fingerprint reader, for a swipe implementation, this is pretty quick. It's easy to miss the reader though, you have to perfectly swipe straight-down in the middle of the button, and if you miss it will tell you to try again. Moving a finger straight-down is kind of awkward, and it's really not something you can do casually like you can with the iPhone's single-press implementation. Samsung has an SDK for the fingerprint reader and, if support for it is built into an app, it can be used as a password replacement. Out of the box it can be used to unlock the phone and to unlock selected "locked-down" apps.

On the back, next to the LED flash is a heartbeat reader. Just fire up the right app, hold a finger down on the sensor, and it will read your heartbeat. Samsung added this feature to all the new Gear models. While it makes sense on something that is always strapped to your wrist, it makes much less sense on a phone. It works—Samsung's health app can tell you your heart rate—but will you ever use it?

Hands-on with the Galaxy S5.

However, the biggest head-scratcher is the new settings screen, which tosses out the normal list view for a grid of circular icons. Samsung redesigned every settings icon as a white silhouette on a colored circle. These are the only icons that have been redesigned though. For instance, the icons in the app drawer are still full-color freeform shapes with no background. The white icons on a colored background remind us of Windows 8. And with the two icons styles being so different, the S5's version of Touchwiz really reminds us of Windows 8, because it looks like two totally different operating systems were piled on top of each other.

One of the truly neat additions to the Galaxy S5 is the new Hybrid auto focus system. It uses a similar auto-focus method as a DSLR, meaning the S5 should spend less time searching for focus and more time snapping pictures. In the extremely bright conditions of Samsung's press event, the auto focus seemed very fast, but that's hardly a thorough test. We'll have to wait for a review unit to really test out the camera.

Enlarge/ The S5 with the back off. The gray rubber gasket on the back keeps it waterproof.

Like the Note 3, the Galaxy S5 uses a Micro USB3 port. This is backwards compatible with USB 2.0, so your old chargers will still work. The Note 3's USB implementation left a lot to be desired, so hopefully Samsung has worked the bugs out on this version. Like all of Sony's mobile lineup, the S5 is water-resistant. Just like Sony, Samsung needed to add a flappy port cover to the bottom of the S5. Of course, the S5 still has a removable back, so water proofing there is handled by a gray rubber gasket that runs around the inside of the removable back cover—make sure it's on tight!

Most of the really interesting features added to the Galaxy S5 will take a lot longer to assess than the limited time we had with the device. Samsung has added lots local dimming features to the Galaxy S5's AMOLED display, and we definitely want to check out the new auto focus system in lots of different lighting conditions. There's also the MIMO Wi-Fi antenna setup, which should provide more throughput (but getting any kind of Wi-Fi at Samsung's event was a challenge). On the surface, Samsung seems to have not changed much, but why should they? They're dominating the market, and unless someone else threatens the Korean giant, they have no reason to move faster than this.

Ron Amadeo / Ron is the Reviews Editor at Ars Technica, where he specializes in Android OS and Google products. He is always on the hunt for a new gadget and loves to rip things apart to see how they work.